For Guru Palitha Lagnas Kethu is favorable
for Shani Palitha Lagnas , Rahu is favorable.
Kuja Vath Kethu, Shani Vath Rahu. Even vice versa also work but Moon must be strong.

For example, Karkataka Lagna, Rahu in 11th will give positive results when moon is strong. But is being in Badhaka Stana for Chara Lagna not yoga karaka. Health wise body may get suffer more.